Recently, consumption of liquefied gas such as liquefied natural gas (LNG) and liquefied petroleum gas (LPG) has been rapidly increasing worldwide.
In particular, liquefied natural gas (hereinafter, “LNG”) is an eco-friendly fuel with low emission of air pollutants during combustion and is increasingly used in various fields.
LNG is a colorless transparent liquid which can be obtained by cooling natural gas containing methane as a main component to about −162° C., and has a volume of about 1/600 that of natural gas. Thus, liquefaction of natural gas into LNG enables very efficient transportation of natural gas. For example, LNG carriers are used to transport (carry) LNG by sea.
As regulatory standards for ships in international organizations and various countries are becoming increasingly stringent, there is also a growing interest in eco-friendly, highly efficient fuels for ships. As a part of this, engines such as a dual fuel diesel electric (DFDE) engine, which can be fueled by gas generated by natural or forced evaporation of LNG have been developed and applied to ships.
Such a ship using LNG as a fuel is referred to as an LFS (LNG-fueled ship). Along with strengthening emission standards for ships and stabilization of LNG prices, LFSs are expected to become more active in construction and operation.